In Mathematica, you would use the ContourPlot3D function for this http://reference.wolfram.com/mathematica/ref/ContourPlot3D.html

It may not be possible to create a 3D plot with multiple contours yet in Wolfram|Alpha, but I haven't been able to do it yet.Wolfram|Alpha doesn't have a defined syntax, so there isn't anything generally wrong with your input.